1. Field of the Invention
The present invention relates to clothes dryer exhaust vent systems, and more particularly to a wall outlet box for a dryer vent exhaust conduit.
2. Description of the Related Art
A clothes dryer requires an exhaust conduit, typically enclosed in a wall cavity, which conveys heated air and lint from the dryer to an external location. Generally, a flexible hose is used to connect the dryer blower to the exhaust conduit. However, if the flexible hose is kinked or crushed, or otherwise altered or damaged, air flow from the dryer can be restricted, resulting in inefficient operation of the dryer. Of even greater concern is the possibility of lint buildup within an altered or damaged hose. Lint material is combustible, and the heat build-up due to blocked air flow can result in fire. In this regard, the U.S. Consumer Product Safety Commissioner estimates that there are 15,500 occurrences of dryer fires annually, many of which are the result of lint trapped in the exhaust duct.
In a common installation configuration, the exhaust conduit within the wall cavity is angled so that it protrudes perpendicularly from the wall surface, and the flexible hose leading from the dryer blower is inserted therein. The diameter of the flexible hose is typically sized to allow for close engagement with the exhaust conduit.
The positioning of the exhaust conduit in the wall usually causes the flexible hose to bend in at least two places when connected because it often does not align properly with the exhaust on the clothes dryer itself. During installation, this connection is initially made and the dryer is then pushed toward the wall. Dryers are usually installed in an area with a limited amount of space and it is extremely difficult to adjust the vent connection after the dryer is installed. To avoid damaging or altering the hose during installation, the dryer is often positioned a considerable distance from the wall containing the exhaust conduit.
The point of connection for the flexible hose usually consists only of the protruding metal conduit. Alternatives to this arrangement are seen in Harpenau, U.S. Pat. No. 5,476,183 and Harpenau, U.S. Pat. No. 6,410,102, which disclose a recessed substantially rectangular box or receptacle to be mounted in a wall which can receive the flexible hose, thereby allowing the dryer to be placed in close proximity to the wall. The box includes a plurality of apertures to receive the exhaust conduit so as to allow for different installation configurations. The box may also be configured to guide the flexible hose into the proper position during installation.
However, installation of such boxes can be problematic, as the installer may have difficulty in supporting a length of dryer exhaust conduit pipe while assembling additional lengths of dryer exhaust conduit. In cases where the rigid exhaust conduit protrudes too far into the wall outlet box, the wall outlet box may not provide sufficient height or space to facilitate the recoiling and storage of the flexible dryer hose. If too much length of dryer exhaust conduit protrudes from the port in the box, it can reduce the amount of recoil space available for the flexible hose and impede the proper connection of the flexible hose to the dryer exhaust conduit.
Additionally, when improper measurement of the length of dryer exhaust conduit needed is made, another possible result is excess length of dryer conduit protruding from the outlet box, resulting in waste of dryer conduit material and increased costs to the installer. Another possible result is that the dryer exhaust conduit fails to sufficiently protrude from the opening, resulting in improper installation of the dryer hose. This can result in increased risk of fire due to venting of dryer lint inside the wall rather than through the dryer exhaust conduit. Typically to get around such problems, the installer can make several detailed measurements to ensure a proper length. However such a task can be time-consuming and not economically efficient.
Therefore, what is needed is a wall outlet box that enables the installer to consistently and accurately determine and provide the proper length of protruding dryer exhaust conduit when installing a wall outlet box, without the need to make detailed measurements or the need to have a third person to support the dryer exhaust conduit from the right distance during installation.